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#!/usr/bin/env python
# -*- coding: utf-8 -*-
#
# This file is part of the Shiboken Python Bindings Generator project.
#
# Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
#
# Contact: PySide team <contact@pyside.org>
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU Lesser General Public License
# version 2.1 as published by the Free Software Foundation. Please
# review the following information to ensure the GNU Lesser General
# Public License version 2.1 requirements will be met:
# http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
# #
# This program is distributed in the hope that it will be useful, but
# WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
# Lesser General Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public
# License along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
# 02110-1301 USA

'''Test cases for virtual methods.'''

import types
import unittest

from sample import VirtualMethods, SimpleFile, Point

class Duck(VirtualMethods):
    def __init__(self):
        VirtualMethods.__init__(self)

class Monkey(SimpleFile):
    def __init__(self, filename):
        SimpleFile.__init__(self, filename)

class DuckPunchingTest(unittest.TestCase):
    '''Test case for duck punching (aka "monkey patching").'''

    def setUp(self):
        self.multiplier = 2.0
        self.duck_method_called = False

    def testMonkeyPatchOnVirtualMethod(self):
        '''Injects new 'virtualMethod0' on a VirtualMethods instance and makes C++ call it.'''
        vm = VirtualMethods()
        pt, val, cpx, b = Point(1.1, 2.2), 4, complex(3.3, 4.4), True

        result1 = vm.virtualMethod0(pt, val, cpx, b)
        result2 = vm.callVirtualMethod0(pt, val, cpx, b)
        self.assertEqual(result1, result2)
        self.assertEqual(result1, VirtualMethods.virtualMethod0(vm, pt, val, cpx, b))

        def myVirtualMethod0(obj, pt, val, cpx, b):
            self.duck_method_called = True
            return VirtualMethods.virtualMethod0(obj, pt, val, cpx, b) * self.multiplier
        vm.virtualMethod0 = types.MethodType(myVirtualMethod0, vm, VirtualMethods)

        result1 = vm.callVirtualMethod0(pt, val, cpx, b)
        self.assert_(self.duck_method_called)

        result2 = vm.virtualMethod0(pt, val, cpx, b)
        self.assertEqual(result1, result2)
        self.assertEqual(result1, VirtualMethods.virtualMethod0(vm, pt, val, cpx, b) * self.multiplier)

    def testMonkeyPatchOnVirtualMethodWithInheritance(self):
        '''Injects new 'virtualMethod0' on an object that inherits from VirtualMethods and makes C++ call it.'''
        duck = Duck()
        pt, val, cpx, b = Point(1.1, 2.2), 4, complex(3.3, 4.4), True

        result1 = duck.virtualMethod0(pt, val, cpx, b)
        result2 = duck.callVirtualMethod0(pt, val, cpx, b)
        self.assertEqual(result1, result2)
        self.assertEqual(result1, VirtualMethods.virtualMethod0(duck, pt, val, cpx, b))

        def myVirtualMethod0(obj, pt, val, cpx, b):
            self.duck_method_called = True
            return VirtualMethods.virtualMethod0(obj, pt, val, cpx, b) * self.multiplier
        duck.virtualMethod0 = types.MethodType(myVirtualMethod0, duck, Duck)

        result1 = duck.callVirtualMethod0(pt, val, cpx, b)
        self.assert_(self.duck_method_called)

        result2 = duck.virtualMethod0(pt, val, cpx, b)
        self.assertEqual(result1, result2)
        self.assertEqual(result1, VirtualMethods.virtualMethod0(duck, pt, val, cpx, b) * self.multiplier)

    def testMonkeyPatchOnMethodWithStaticAndNonStaticOverloads(self):
        '''Injects new 'exists' on a SimpleFile instance and makes C++ call it.'''
        simplefile = SimpleFile('foobar')

        # Static 'exists'
        simplefile.exists('sbrubbles')
        self.assertFalse(self.duck_method_called)
        # Non-static 'exists'
        simplefile.exists()
        self.assertFalse(self.duck_method_called)

        def myExists(obj):
            self.duck_method_called = True
            return False
        simplefile.exists = types.MethodType(myExists, simplefile, SimpleFile)

        # Static 'exists' was overridden by the monkey patch, which accepts 0 arguments
        self.assertRaises(TypeError, simplefile.exists, 'sbrubbles')
        # Monkey patched exists
        simplefile.exists()
        self.assert_(self.duck_method_called)

    def testMonkeyPatchOnMethodWithStaticAndNonStaticOverloadsWithInheritance(self):
        '''Injects new 'exists' on an object that inherits from SimpleFile and makes C++ call it.'''
        monkey = Monkey('foobar')

        # Static 'exists'
        monkey.exists('sbrubbles')
        self.assertFalse(self.duck_method_called)
        # Non-static 'exists'
        monkey.exists()
        self.assertFalse(self.duck_method_called)

        def myExists(obj):
            self.duck_method_called = True
            return False
        monkey.exists = types.MethodType(myExists, monkey, SimpleFile)

        # Static 'exists' was overridden by the monkey patch, which accepts 0 arguments
        self.assertRaises(TypeError, monkey.exists, 'sbrubbles')
        # Monkey patched exists
        monkey.exists()
        self.assert_(self.duck_method_called)

if __name__ == '__main__':
    unittest.main()